The Doctor's Daughter
by dragonwriter24cmf
Summary: Avenger's Endgame/Captain Marvel AU. In which Carol Danvers survives contact with the Tesseract due to a unique legacy. Namely, that of being the biological daughter of The Doctor and River Song. When Thanos threatens Earth with the second Snap, she calls on her father for help. The Doctor may now be female, but she still won't allow threats to her favorite people. Or her daughter.


**The Doctor's Daughter**

Most people, if they'd come in contact with the raw power of an Infinity Stone, wouldn't have survived. Absorbing that kind of power isn't healthy. Most people, if they had survived, would have panicked. Or gotten trigger happy with their new abilities.

But then, she isn't most people. She never has been, and she's known that since she was fourteen. Since she came home from school to find her parents in the living room with a tall, thin older looking gentleman, who introduced himself as the Doctor.

No name. Just the Doctor.

Introductions out of the way, he waves her to a seat with her parents, and proceeds to reveal three things. One, she's adopted. Two, He's her father, even though he looks old enough to be her grandfather. Three, he isn't human.

The not human part is the easiest to handle. Who hasn't heard of aliens on Earth? And mutants. He lets her listen to his heartbeat, the odd quadruple thump that indicates he has two hearts instead of one, and after that she's convinced that he's telling the truth.

The other two pieces of information are a little trickier. She's known kids who were adopted, but she never thought she'd have to ask those questions. Why? Why did they leave her? She never thought she'd feel that ache of knowing that someone gave her up. She wants to understand, so she settles into the embrace of her parents (adopted parents), while the Doctor makes an attempt at an explanation.

An attempt, because it is, quite frankly, a bizarre explanation. She's not sure she really understands, but if she does, then the story goes something like this:

Her mother, River Song, was the daughter of two of the Doctor's traveling companions (which, okay, a bit creepy, cradle robbing much?). The Doctor is a time traveler, who wanders through time and space in his ship, which he shows her through the window. It looks like a blue phone booth. He swears it's more, and, okay, she can believe that. So, anyway, her mother's parents were human, but because she was conceived, born and raised under the influence of the time vortex and the Doctor's ship, her mother wound up becoming a hybrid, with some Time Lord characteristics. She and the Doctor were married, something about timeline convergence that she doesn't understand, but they were both time travelers, and they'd already discovered that their personal timelines weren't on the same path, just intersecting here and there. Which, okay, weird, and that's a thought to give her headaches, thank you.

But, to get to the point, her parents finally got to spend some time together. A night on Darillium. But that one night was the equivalent of 24 Earth years (and she's so glad they covered solar cycles in class, because it helps her make sense of that part, at least). And while they were there, she was conceived. Unfortunately, it was near the end, too close for them to have raised her to adulthood in the time they had remaining. So...decisions.

The Doctor swears they wanted to keep her, that they loved her. And she believes him. His eyes say it all, lonely and grieving for what was lost, a loss he feels much more keenly than she could. But, despite that, neither of them wanted her to grow up without one parent. And neither of them wanted to expose her to the dangers that seem to inhabit their lifestyles. Time travel and exploring the universe isn't really a good life for an infant, or even a younger kid. So, after much discussion, they reluctantly decided to have her adopted, to give her a chance at a long, healthy, and somewhat stable life. So the Doctor contacted some friends he had on Earth (something about a government agency in England that deals with temporal issues, top secret of course). And those friends found the Danvers, childless but wanting children, and willing to take in a babe who wasn't quite human. The agreement was that the Danvers would raise her, but they would tell her the truth before she became an adult. They would decide when, and call the Doctor.

And that's the whole story. Well, most of it. She does want to know why he wasn't around when she was younger, at least visiting. His answer?

"I didn't want to lie to you. That would have made it worse, if I'd told you I was something I wasn't. And if I'd told the truth...I thought it would be easier, if you had a strong relationship with your family before that."

Okay. She's not sure she agrees, but okay.

They talk a little longer. He shows her the inside of his ship (and isn't that a head-rush and a half). Before he leaves he gives her a phone, like the ones her parents have, that can contact him no matter where or when he is. He promises to visit, and then he goes.

It takes a few days (or weeks), but she comes to terms with the whole thing and decides that, no, she's not angry at her birth parents. Would she have liked to have a say? Yeah, sure. But she was a newborn. And the Danvers are good parents, and she loves them, and she's not sorry she can call them mom and dad. And maybe hopping through all of space and time sounds cool (okay, it definitely sounds cool), but she doesn't regret having a life with friends, and school, and athletic clubs, and all the mundane things. She's glad she got to experience slumber parties and football games and stuff like that.

After that, everything is okay. She calls her birth father (father, not dad, dad is her human father who raised her) every so often. Sometimes, he calls her. He pops in, every now and again, with his blue phone box/ship.

When she's sixteen, she learns to drive a car. After she gets her license, she gets the Doctor to teach her how to pilot the TARDIS. Which is a lot more difficult than it looks. But it's fun as all get out, way better than a sports car.

When she turns eighteen, becomes an adult, he gives her a trip to a time and place of her choosing. She asks to see Darillium, the place she was born. He takes her to the Singing Towers, to the little restaurant. It's beautiful, and she keeps a picture with her when she leaves, to remind herself of where she came from, even if it's not where she was raised.

When she turns twenty-one, a full adult, he takes her into the TARDIS and sits down with her, and tells her about himself and her mother. He tells her about Time Lords, about Amelia and Rory Pond. About regeneration, and about how River Song and her mother were kidnapped by something called the Silence, and how he waged war to rescue her. He tells her about the things he's done, in his past. Wonderful things. Terrible things. He tells her how her mother passed away, saving the lives of thousands of innocent people, while a part of her lives on, inside the cyber mind of a library shrouded in darkness. He tells her about his Companions, his friends. The secrets of the TARDIS. He tells her about Daleks and Cybermen and the various dangers of the universe.

He takes her to visit past friends, Vastra and Jenny and Strax. And current friends, Bill Potts and Nardole. She likes Nardole, even though he's kind of fussy, because he tells her stories of her mother, stories the Doctor can't tell her, about the times they weren't together.

It's a lot to take in. It's scary, and it's awe-inspiring, and she'd be lying if she said she doesn't feel overwhelmed long before he finishes talking. Even so, she hangs onto every word.

Before he leaves, he gives her a key to the TARDIS. So she'll have access if she ever needs it. And so she can inherit it, if he passes away before she does.

It takes her a few days to settle everything in her own mind, but when she does, she's okay with it. Despite the fact that some of the things he's done make her blood run cold (activating a weapon that destroyed 95% of a race and locked his own people into a sealed dimensional bubble, for one), she thinks that...well, she's pretty sure her birth father is a hero. And that's...that's something to be proud of, even if she's not sure that he's proud of himself.

Her birth mother is a hero too. And now she has pictures, and she knows that her birth mother was also smart and kind and sarcastic and funny. And beautiful.

She can live with that. And she'd be lying if she said their legacy didn't influence her, but her family is okay with that, and so is she.

And then she gets exposed to the Tesseract. An Infinity Stone in a box. After she recovers, and after she sorts out the mess it made of her brain, gets her memories back, and fixes the situation, she does the only thing she can think of. She calls her birth father, then turns up at his office, where he's been teaching this and that to college students for the past several years.

It doesn't take long to figure out that she survived because of her Time Lord genetics. She kind of suspected that to begin with, once she remembered everything, but the Doctor confirms it, and explains that the Tesseract energy fused with her latent Time Lord powers and made them active, though modified for her human biology. He takes her into the TARDIS, and together, they figure out limits and abilities, and she gets used to her new powers. Like flying in a vacuum (something that terrifies the Doctor when she tries it).

It takes two years to learn about her new powers, their quirks and their drawbacks and their uses. That being said, it's a little disconcerting when she steps out of the TARDIS into the office only an hour after she came in. As the Doctor says, that's the nice thing about time travel. Forever in an instant.

Going back to her old life is impossible. In two years, she's seen the universe, discovered things she didn't even know existed, learned things about herself she never expected. Which is how she winds up promising to help the Skrulls find a home, and going from there to don the mantle her birth Father has been trying to retire from. A guardian. A helper. As Bill puts it: "sometimes, there's just a person, you know? That's all it takes for good to win. Someone who goes around helping, yeah?"

She's now that someone.

She keeps in touch with her family, the Doctor, Nardole, Bill. The Danvers, and her close friends on Earth. She hears about the formation of the Avengers, and she laughs. She hears about other Infinity Stones popping up, and keeps an eye out. She hears about the Asgardians, and the Guardians of the Galaxy. Fury keeps her updated, and the Doctor links her into the TARDIS so she can scan the various timelines and keep an eye on things.

And then….And then THE SNAP happens. Thanos gets the Infinity Stones, creates the Infinity Gauntlet, and destroys half of all life in the universe. And everything goes to chaos. Falls apart.

The first thing she does is call the Danvers. Her mother is gone. The second thing she does is call her birth father.

He's okay, tucked in the vortex when it happened with his human friend and Nardole. And she can't stop the bitter question that emerges. "Why didn't you stop this?"

He's a Time Lord. Why didn't he see this coming and prevent it?

"Sometimes, things happen that can't be stopped. Fixed points in time. I know, it's not comforting and I wish it weren't so. But this...this is even worse. It's a fluid point. The universe, all the timelines – they're in flux. I can't see anything for certain. Not right now."

She pulls up her TARDIS connection, and she can see what he means. Time seems to be shifting, like the flow of liquid mercury. "What do we do?"

"Hold things together until a solution presents itself."

"How long will that take?"

He makes a frustrated noise. "I don't know. A day, a month. A year. A century. I spent three hundred years waiting once."

Three hundred years. She hopes it's not that long.

He sighs. "At least it's not a quantum-continuum loop. Those are worse."

"A what?"

"Time/space prison. Nasty things. You have to be released or find the back door, and that's usually difficult. Very difficult. Takes almost literally forever."

She breathes out. Breathes in. "Okay. So...hold things together. We can do that. Will you be helping?"

"Yes. I will. As much as I can, at any rate."

"Good." She says goodbye and hangs up, then begins looking for where she's needed most.

The next five years are...difficult. Tony Stark, their best hope for figuring out an answer, goes into seclusion after nearly dying while trying to get home. Thanos is killed, but not before he destroys the Infinity stones. All across the universe, cultures and peoples fall apart, fall into despair and disrepair. She helps where she can, with the remnants of the Avengers and the Guardians. It's a universe full of bitterness.

She keeps touch with the Doctor, sort of. It's more like phone tag, honestly. She sends messages to the TARDIS, gets messages back. During the first six months, she asks about the possibility of undoing THE SNAP. Going back in time and preventing it. His return reply is long, and boils down to something like: 'The Snap is a fixed point in time now. Too deeply ingrained and too widely observed to alter without catastrophically unmaking all of reality.'

So that's out.

Five years after The Snap (as the survivors who were there tend to call it) something happens. A man named Scott Lang shows up, released from an accidental quantum state. He's no scientist, but he is smart. And more importantly, he has news. And an idea.

Time travel. Pick up the Infinity Stones. Use them in their current timeline, then put them back to avoid screwing things up too much.

She listens, then calls the Doctor. There's an odd ping on the line, so she looks into the TARDIS connection instead. And yeah, it looks possible. It's an idea. It won't unmake the universe, since they're doing a delayed reversal of The Snap, rather than trying to prevent it.

They can do this.

It would be easier with the TARDIS. However, she doesn't want to disturb whatever the Doctor is doing. She knows better. She's made that mistake once or twice before (before Thanos) and never with good results. So she leaves the Avengers to assemble a time machine with the help of Thor and Scott Lang and Rocket. She goes to look for allies, because they're going to need all the help they can get, if this works. Half a universe of people are going to come back to an existence that's spent five years without them, and not for the better. People need to be warned, and need to be helped.

The monks that once followed Stephen Strange are apparently already aware, and working on plans that their former leader shared with them. The people of Wakanda, on the other hand, are overjoyed and spring into action. The same is true of the people of Asgard, who hate what Thanos has done with more passion that she'd believe possible, if she didn't know what he'd done to them even before The Snap.

As luck would have it, it's a good thing she's calling on allies. Because Thanos finds out about the time machine, and the time travel, and the Infinity Stones.

The Snap gets reversed.

Then Thanos appears and levels the Avengers home mansion. The Hulk's already been hurt by the gauntlet, Nebula has apparently been switched with her past evil self, and the rest of them barely survive having a building dropped on them.

She's lucky she has the TARDIS link-up. And Strange's brothers-in-mystic-arts. Otherwise, the fight would be over before it begins. But even with that, as she comes through with their gathered allies, all the heroes of Earth and beyond, her heart sinks.

Chitauri they can handle. There's a lot of them, but they've fought the Chitauri to a standstill before. Once in Wakanda and once in New York.

Thanos' children are a bigger problem. Far more dangerous. But they're still capable of being defeated. They can be beat. And Gamora has already defected, which helps. Also, Nebula has apparently defeated evil Nebula.

But then there's Thanos himself. The Titan. And that...that's a problem. This isn't a tired Thanos. This is one who is strong, arrogant, ready. Assured of his victory. And of his righteousness and his powers.

He's also determined to kill them all. The Thanos of before had a grudging respect for humans, for them, the heroes of Earth and the galaxy. This one has only cold contempt, anger at their determination to thwart his plans. This Thanos plans, not balance, but total annihilation. And unlike the heroes, he's coming to the battle fresh and rested. The revived are in the best of condition, and they're not at a hundred percent.

It doesn't take a genius to see that a lot of people are about to die. And victory, if it's even possible, will come at a high price.

They need something to tip the balance.

As the two forces stand gathered, watching the meeting between Steve Rogers, Thor, and Thanos, she yanks out her phone and makes a call, praying that she'll get an answer.

One ring. Two. And then: "Hello?"

She doesn't recognize the female voice. "I'm trying to reach the Doctor."

"Yeah. This is...oi, is that...Carol?" There's an enthusiastic, wordless sound. "I've been meaning to get in touch you know, bit chaotic and all that..."

"Are you the Doctor?" She doesn't have time for chit-chat. "Or do you know him?"

"Oh...right. Regeneration. Sorry about that. Forgot you wouldn't know yet. What do you need?"

"You should be registering a huge temporal disturbance on Earth at my spatial-temporal location."

"Yeah. We were just looking at that." She wonders who 'we' is, but this isn't the time to ask.

"Thanos is here. From the past. He's here and he's planning to kill everyone in the entire universe. Unless we stop him." She pauses, because she hasn't asked since she transformed, then says the magic words. "We need help."

There's no levity in the voice that replies, only calm reassurance. "Right. I'm on my way."

She hangs up, knowing the connection won't really hold while the TARDIS travels the vortex, and stows the phone in a pocket. Stephen Strange, standing nearby, cocks an eyebrow. "Doctor?"

"My father." And then there's no more time to talk, as the two armies rush towards each other and battle is joined.

Battle is...chaotic. She's seen chaos in all it's many forms, but this is worse than most. Thanos' ships, Thanos' children, the Chitauri, and Thanos himself. It's a melee with only one goal in mind for either side. Get the Infinity Gauntlet and use it to stop the other side. The Defenders are trying to get it into the quantum portal that Lang has, while Thanos and his troops are trying to get it to him, to use.

And then the portal is destroyed by a missile, and it's simply a game of keep away, with the universe's worst consequences.

If Hulk hadn't already been hurt using the gauntlet, she'd suggest giving it to him. Without him, though, who else can? Few people can even handle _one_ Stone, let alone all of them. The Asgardians could, maybe, but Thor's no power user and Loki...who knows? Vision is gone, destroyed. She has no idea about the people of Wakanda, or Stephen Strange and the monks.

Not that there's really a lot of time to think about options, what with fighting against all of Thanos' armies.

She's not surprised when she comes face-to-face with Thanos. She's one of the few who might be able to handle him, with her enhanced strength.

Or so she thinks until he sends her flying, pummels her into the ground. She lands, winded, and thinks she's about to become a casualty of battle when Thanos jerks to a stop. His weapon goes flying. He whips around in surprise, and she follows his gaze.

There's a woman standing there. There's dirt on her face and her clothes (odd clothes at that, and nothing like something that should be worn in battle) and she's a complete stranger, but...she's _familiar._

Straight blond hair, cut chin length. Blue eyes and a strong chin and _that_ nose. Thin but strong build. The woman looks like she could be her sister, and she doesn't have to ask to know who she really is.

Thanos does. "And who are you, little mortal?"

The woman tosses her head with a smile. There's an edge to that smile, and if she didn't know already, she would by that, even before she speaks. "I'm the Doctor."

"The Doctor. Of what?" Thanos smirks.

"Not what. Who. But never mind that. You..." The woman shakes her finger at him. Shakes. Her . Finger. At. Thanos. "You're causing a bit of ruckus round here. And I'll thank you to stop. See, this planet, these people...they're under my watch, and I'll not have you meddling with them any more." She waves a hand. "Call off your people. Or I might just get really irritated."

There's a glint in the Doctor's new eyes, and suddenly she remembers her birth father (mother now?) telling her about the Time War, and how he earned the name The Oncoming Storm. When he told her those stories, the Doctor looked tired and ashamed and wounded in a way she's only seen in traumatized war veterans. This Doctor looks like she's come to terms with that title. With who she is. What she is.

Thanos doesn't have her knowledge though. He just smirks. "Stop me then. If you think you can."

"Oh, I can. And you aren't going to like it." The Doctor flicks her hand, and a gleaming instrument tips into her grasp.

Thanos charges. The Doctor whirls out of the way and flicks the device. Thanos goes flying.

Oh. Right. Sonic screwdriver. She has no idea what all it does. But apparently, it's an effective weapon. Or tool. Or...whatever.

Stark lands beside her, battered and bruised and guarding the Gauntlet. "Friend of yours?"

"My father, actually."

Stark blinks. "Uh...hate to break it to you, but that is actually a woman, and last I checked..."

"It's complicated." She smashes a Chitauri who gets too close. Stark slams another two with repulsor beams. "Plans for that thing?" She tips her head at the Gauntlet they're both guarding now.

"Well, portals are all busted, not seeing a chance to build a new one anytime soon, so I'm kinda open for a plan B. Or, you know, any plan, since only Strange seems to know what's going on, and he's not talking. Something about 'what has to happen won't' if he tells, which, I call bullshit, but..."

Stark keeps talking, but she stops listening, because she understands.

Someone has to wear the gauntlet and stop Thanos. For good. But that's…

It's suicide. Even for her. There's just too much power there. Strange knows that someone has to volunteer to die. And sure, they're surrounded by heroes, but not everyone has the mental strength to wield the Gauntlet, or the physical strength to survive long enough. Never mind the battle raging around them, which is a pretty heavy distraction.

How do you ask someone to die for the universe? Who do you ask, and how do you decide?

Thanos makes a furious sound, and a small, lean figure goes flying. A pale gray coat flares out like wings, and the Doctor goes staggering back. Her nose is bleeding, and she's limping slightly, but she doesn't look beaten. Not yet.

The answer clicks into place. Time Lord. Or Lady. She called her birth parent because he (she?) is stronger than anyone else she's ever known. This is the Oncoming Storm. The entity known across the universe, spoken of as legend and whisper in the farthest corners of creation. Wielder of powers she can't even comprehend. If anyone could survive wielding the gauntlet…

She blasts another Chitauri. "Can that shrink?"

"Housing's fused."

"Can you make another one? Like, right now?"

"Yeah, pretty simple, but..."

"Do it." She blasts another Chitauri, then another, protecting Stark to give him breathing room. "I've got an idea."

"Yeah, okay, if you say so." Stark ducks down.

Protecting him is harder than it looks. Fortunately, there are others watching out for them. Steve Rogers and Thor, who have both joined the Doctor in fighting. The Valkyrie. The king of Wakanda, as the Black Panther. Stephen Strange. They're standing in the eye of the battle, the eye of the storm, with defenders and foes all around.

It feels like forever, but it's probably only a minute or so before Stark pops up. "Got it." He's holding a thin gauntlet with the gems flaring, and one hand is bare. "So, plan?"

She looks for the Doctor, just in time to see her birth parent go flying again. "Get it to her." She points. "Tell her to use it."

"Seriously? That's the plan." Stark doesn't look impressed.

She meets his eyes. "Trust me."

"Right. Trust. Great. Let's roll with that, while we execute crazy plan 101. Sure." But he fires up his repulsors.

Traversing a battlefield with the gauntlet isn't any easier when they aren't aiming for the portal. Halfway there, she finally gives in to frustration and shouts. "Father!"

The Doctor looks up. Blinks at her with wide eyes in a soot stained face. Then ducks out of the battle with Thanos to dodge five Chitauri. She hits Ebony Maw with a sideswipe and a sonic screwdriver to the eyes that makes him jerk back with a howl, and then plows into their group. "What is it?"

She snatches the gauntlet from Tony. "You can use this. To stop Thanos."

The Doctor eyes the gauntlet. "Not sure that's wise."

"It's the only way. If you don't, he's never going to stop."

Or someone else will, and they will die. But she doesn't say that. She can't.

The Doctor looks to where Thor and Captain America are fighting Thanos. Then back, as Stephen Strange and Iron Man join in. "You have to be sure. Very sure. You know what you're asking me to do, don't you?"

She does. The gauntlet is a weapon as powerful as the Moment. Maybe even worse. And she's asking her parent to decide the fate of the universe, to possibly commit genocide. She's definitely asking her to risk her life to do so. "I know. But this...this is the only way." It isn't, but it's the best way, and she believes that with all her heart.

Strange falls back, flung by Thanos. He eyes the gauntlet, then the Doctor. And he nods. "Do it."

The Doctor flicks her eyes over the battlefield. Then nods and takes the gauntlet.

The gauntlet folds down over her slender arm and erupts into coruscating light. Lines of pure power, pure radiance, twine around the arm. The Doctor gasps and doubles up around her arm. "Oh, that's...that's a bit much that is..."

She looks like she's going to faint. Or collapse.

Golden radiance blooms to life in the center of her chest, flows outward to meet the power of the Gauntlet, and within that light, the Doctor steadies. Breathes deep and straightens. Luminescent eyes flicker over the battlefield again. She lifts her hand, and everything...stops.

Just stops. Like time is frozen.

The Doctor moves forward, touches her, and she finds herself able to move. "What…?"

"Stasis lock. But...I'd rather have a witness for this, and I thought you might…." The Doctor looks vulnerable and frightened, even with the glow of the gauntlet and whatever powers she's mustered.

"Sure. No problem." Strange can see, and Stark is probably recording with his suit, and there are probably several people watching off to the sides, but she understands.

The Doctor stalks toward Thanos, touches the Titan and he staggers back, eyes wide. "What have you done?" His eyes flick to the gauntlet. "How..."

"I told you. I'm the Doctor. And this world, well, this reality really, is under my protection. I'm not about to let you mess it up twice. Wouldn't have once if I hadn't been retired, and then a bit indisposed." The Doctor tilts her head. "Now, you've made quite a mess of things, and I'd rather like to know why before I decide what to do with you."

Thanos scowls, and it's obvious that he's considering just charging the Doctor and trying to take the gauntlet by force. The Doctor cocks her head at his shift in stance and shakes her head. "And none of that, thank you." She waves, and Thanos drops back onto a seat of stone and wreckage with a snarl.

"The universe needs balance. Too much life, too much destruction. I had planned to remove half the life in the universe, but coming here has made me see. A weak universe, too busy whining for those freed from mortal concerns to understand their salvation, to allow their own enlightenment. What's needed is a true cleansing."

"Seriously?" The Doctor scowls, hands on her hips. "Honestly? Why do so many people think killing people is the answer? It doesn't solve much of anything." She waves her hand in an agitated fashion, ignoring the little sparks that shoot off her fingers. "I mean, even if you did go through with this mad plan...it's not going to stop the universe. Everything lives, everything dies, that's just the way things are! You can't just...commit genocide and expect to stop it!"

"Balance would enable the universe to live longer." Thanos gestures. "Look at this world, this world you claim to protect. They use up their resources. Within a generation, maybe two, this world will no longer sustain them. And then what? They will die. Perish. Or be lost to the void."

"No. They won't. Humans are...they're adaptable. That's one of the things that makes them so amazing. I've seen the future, and they'll flourish." There's not a trace of doubt in the Doctor's voice. "Whole worlds of them, galaxies of them. It might not be easy, or safe, or simple, but that's what's wonderful about it. Don't you understand that? What people can accomplish when they're alive, when they have hope and time and inspiration...that's the whole point of...of everything!" She waves her arms again.

Thanos sneers. "I see you are a fool of an idealist."

"Crimey! You're like a ruddy Dalek, you are." The Doctor scowls. "Always wanting to destroy everything, no respect for the way things are meant to be. You just...you don't understand anything about this universe. Or anything." She shakes her head. "I don't like killing, but I won't let you keep on doing things like this." She meets Thanos' eyes. "This is your last chance. Withdraw, or I _will_ stop you."

"Even if you do, there are others." Thanos sneers again, and his eyes are cold in challenge.

"And I'm the Doctor. I protect people. If there are others like you, then I'll be there to stop them too." The power of the gauntlet flares again, adding an edge of power to the words and making the air thrum.

Thanos rises, glaring. "You haven't got the stomach..._Doctor_." The last word is spit with venom and disdain. "You talk too much. You haven't got the _resolve_. Or the strength."

Something terrible sweeps the Doctor's face. Something cold and ageless and painful. Grief. And rage. Something every bit as awful as the twisted hatred and blind determination in Thanos' eyes. Perhaps worse, because it's powered by something infinitely more dangerous than his coldness.

It's love. The kind of love that could sweep the universe apart.

She's always wondered, about what could make the Doctor become the Oncoming Storm. Now she sees, and she wishes she didn't. It's raw and it's awful, it's a form of madness and it cuts to the bone.

Thanos takes a step back, uncertainty clouding his expression for the first time. Then he rallies. "Go on then, if you think you can."

The Doctor lifts a hand, and the gauntlet flares.

Then...she Snaps.

Power sweeps the field. Where it finds Chitauri or Thanos' children, it transforms, to rock. Where it finds Defenders, it heals. Leaves them whole and hale and, in some cases, gasping with the shock of being resurrected.

Thanos is the last, left to watch his army become nothing before the transformation overtakes him. Then every last statue disappears in a flash. And everyone else stumbles back to life.

It's Stark, predictably, who asks the question. "Where'd they go?"

"Little place I know. Figure they'll be welcome. Place called Skarro." She's breathing heavily. "Daleks don't like visitors. Or statues. Or much of anything, really. Even if they don't get blasted to bits, they'll just be buried and left to rot."

"Why not just kill them?"

"Not really my style." The Doctor heaves out a breath and, with a huge effort, shoves the gauntlet off her hand. "Oh, that was…oh, I am really not made for that."

The golden glow hasn't faded. In fact, it's getting worse. Brighter. Wilder.

Stark stares. "What's going on? I thought that was the gauntlet."

"No. Regen...regeneration..." The Doctor staggers, falls to her knees. "Oh...really don't want to do this right now...I just got the hang of this one..."

She kneels beside her parent. "How can we help?"

The Doctor looks up as the glow subsides briefly. "Actually…could use a bit of a grounder, if you don't mind...DNA lock…" She gasps as the glow returns. "Might want to hurry."

"How?"

"Your blood. Mine. Mix and hold on."

That seems simple enough. Or it would be, if she hadn't been healed by the gauntlet a moment ago. Still. "Stark. Sharp object, now."

Tony produces an edge of metal from his outfit, and she slices her arm. Then the Doctor's. She presses the bleeding gashes together, reminded of a time in her childhood when she and her best friend performed a 'blood sisters' ceremony.

The bloody gashes touch, and she locks her hand around the glowing arm of her parent.

Just in time. The golden light rises up in a wave and explodes outward from her parent's face and hands. Stark, Captain America, and Stephen Strange are all knocked backward, and off their feet. People in a several yard radius stagger and there's one yelp that she identifies as Peter Parker falling off a rock nearby.

Then it's over, and the glow sinks back into the Doctor's skin, leaving her breathless and sweaty, but apparently healed and healthy. She lets out a long breath. "Oh. Well." Tosses sweaty blond hair back from her face and collapses the rest of the way to the ground. "Reckon I need a rest after that." And then she passes out.

It seems fair. She feels like she could use a nap herself. But there's things to be done.

People are collected, forming little groups. Tony is hugging his wife, and all around people are meeting up and greeting each other. Those who were killed by The Snap, the first snap, are getting updated on what all has happened since. Tearful reunions are happening all around. There's crying, shouting, some slapping and punching and hysterics.

Eventually, they all go to Wakanda, since the Avengers home is rubble, and Wakanda has resources to feed a bunch of battered, tired heroes.

The Doctor is put in a bed to sleep off whatever happened. Later, after everything is at least sort of settled, she borrows the sonic screwdriver and takes it, with her key and her phone, and summons the TARDIS. It turns out to be occupied by a young woman, a young man and his grandfather, all of whom are very confused. Apparently the Doctor landed the ship, went through the door and engaged an emergency protocol that sent them somewhere else and locked the TARDIS doors.

Explaining takes time. They take it surprisingly well, having apparently had some adventures with her parent before this, and join the throng in Wakanda. The young woman introduces herself as Yaz, British police officer.

She introduces herself as Carol Danvers, the Doctor's Daughter.

She doesn't bother to explain that the Doctor was a man when she was born. Not only is it complicated, but she's already explained to way too many people, including Stark and Strange, both of whom want to know, in detail, how her biological father is now a woman, and also not human.

The Doctor wakes up several days later, looking none the worse for the wear. She spends another two days exploring Wakanda, before offering her assistance with setting things right.

Thor has already returned to New Asgard, with his people. Stark is making plans to return to his cabin with his wife and daughter. Everyone else...well, there's a lot of rebuilding to be done. All across the universe. The people may be back, but there's still the results of five years of absence and grief and decay to be dealt with. Plus, as Banner points out, the Infinity Stones have to be returned to their proper places in the time-stream, to avoid any complications.

After some discussion, it's agreed that the Doctor can handle that task, with Bruce Banner and Captain America helping.

There aren't a lot of tearful goodbyes between them. But she gets a hug, and gives one in return. "Hey. Promise to keep in touch? No more phone tag."

The Doctor grins, with a shy, sheepish smile. "I'll do my best. Afraid that's the best promise I can make. But..." She takes her arms. "I will come when you call. I hope you know that."

"Yeah. I do." And she does. She knows if she really needs a hand, or even just a friendly presence beside her, or a place to rest out there in the black of space, that the Doctor, her parent, will be there.

Of course, there are still things – she did ask the Doctor to effectively commit genocide with Thanos. It's a bit awkward to think about. And there are other issues between them. Such as that regeneration. Did borrowing her DNA make her father her sister? Does she have regeneration powers now? Is her parent more human now? Are there side effects?

But those are questions for another time, and another place. Right now, the universe needs it's heroes. All it's heroes.

The universe needs the Doctor.

And the Doctor's Daughter.

_**Author's Note:**__ I watched Avengers: Endgame. And the latest season of Doctor Who. And then I took a lot of cold medication, and this attacked me in my sleep. Yes, I am aware that I may have fudged a few details about Captain Marvel. I beg your indulgence. And hope you enjoyed._


End file.
